1. Field of the Invention
The present invention relates to a swivel control apparatus for controlling a vehicle headlight which is disposed in a front part of a vehicle, and has such a configuration that a light axis thereof is laterally adjustable.
2. Description of Related Art
There is known a headlight having a configuration in which a swivel angle of a light axis (light distribution direction) thereof is adjustable. Such a headlight is controlled by a swivel control apparatus such that the swivel angle is varied depending on a steering angle of a steering wheel of a vehicle or a road curvature ahead of the vehicle obtainable from a road map data. For example, refer to Japanese Patent Application Laid-open No. 2006-69521. Such a control makes it possible that the illuminating direction of the headlight well coincides with the viewing angle of the driver.
However, a road curvature included in a road map data indicates a curvature of a width-direction center of a road (a curvature of a centerline in the case of a centerlined road). Meanwhile, in most cases, a vehicle travels along a line outwardly or inwardly deviated from the width-direction center of the road. Accordingly, the above described conventional swivel control apparatus has a problem in that it often occurs that the viewing angel of the driver and the illuminating direction of the headlight do not accord with each other.